1. Field of the Invention
The present invention relates to an image pickup apparatus and a fingerprint recognition apparatus, and in particular to an image pickup apparatus and a fingerprint recognition apparatus which have a light irradiation unit for irradiating light to a photographing object and an image pickup element for receiving reflected light or transmitted light from the photographing object and generating an electric signal corresponding to an amount of received light.
2. Related Background Art
Conventionally, as a fingerprint collation apparatus, for example, Japanese Patent Application Laid-Open No. 5-81412 discloses one in which a microcomputer corrects a trapezoidal distortion of a fingerprint image for registration or collation according to a magnification representing a degree of distortion, which is determined from a trapezoidal distortion of a reference figure photographed image based upon a reference figure, and after setting this corrected fingerprint image as a registered fingerprint image or a collated fingerprint image, collates both the reference figure photographed image and the registered fingerprint image or the collated fingerprint image. In addition, Japanese Patent Application Laid-Open No. 10-105708 discloses an image collation apparatus which is applied to, for example, a fingerprint collation apparatus and, when converting a video signal into a binarization signal based upon a predetermined threshold value to judge conformity or non-conformity between first and second images, corrects a signal level of this threshold value to correct unevenness of an amount of light in an optical system.
However, there is a problem in that the above-mentioned fingerprint collation apparatus needs a complicated arithmetic circuit and a large-scale memory in order to perform data correction, which leads to lengthening of processing time and increase in costs.